Shearing machine for dismantling a large aircraft and working vehicle for dismantling a large aircraft

ABSTRACT

As shearing blades of a first jaw portion, a shearing machines includes: a tip blade; a pair of first parallel shearing blades bent at an obtuse angle to the biting direction of the tip blade and disposed both sides of the blade width; and a pair of second parallel shearing blades bent at an obtuse angle to an attaching portion of the first parallel shearing blades and disposed on both sides of the blade width. As a tip blade, the shearing machine includes: a point blade a pair of tip tapered blades disposed on both sides of an end portion and whose blade width is increased toward the rear end; and a pair of tapered blades bent at an obtuse angle to an attaching portion of the rear end portion of the tip tapered blades and disposed toward the first parallel shearing blades.

RELATED APPLICATION

The present application is National Phase of International ApplicationNo. PCT/JP2018/040307 filed Oct. 30, 2018, and claims priority fromJapanese Application No. 2018-033247, filed Feb. 27, 2018, thedisclosure of which is hereby incorporated by reference herein in itsentirety.

TECHNICAL FIELD

The present invention relates to a shearing machine for dismantlinglarge aircrafts suitable for dismantling large aircrafts, such asairliners, using a high-strength aluminum alloy or the like and aworking vehicle for dismantling large aircrafts equipped with theshearing machine.

BACKGROUND ART

In recent years, various objects to be scrapped, including constructionwaste materials, such as reinforcing bars and window frames for sashwindows, and piping waste materials, such as distributing water pipesand water supply pipes, as well as discarded automobiles, have beenincreasingly accumulated here and there. These objects to be scrappedcannot be coped with by ordinary dismantling work and are waiting fordismantling. Meanwhile, with respect to dismantling and cutting work formarine structures, steel buildings, plants, large vehicles, and thelike, cutting machines have been developed. These cutting machines areconstructed by equipping an automotive vehicle with a large steelmaterial shearing machine and intended to be dispatched to a cuttingwork site, cut steel materials or the like and load a truck or the likewith the materials, and transport them to an ironworks or the like asraw materials. Such a cutting machine is equipped with a hydraulicallyactuated boom swivelably and lowerably/raisably mounted on an automotivevehicle and a shearing machine for cutting attached to the tip of theboom and remotely opened and closed.

The shearing machine for cutting includes: a frame that can be attachedto a boom structure; a pair of jaws for workpiece destruction having anattaching portion; and a jaw attaching means for attaching these jaws tothe frame. The jaw attaching means is for attaching both the jaws to theframe such that the jaws can be mutually swung around a sing axis. Thejaw attaching means has a pin portion for detachably attaching the jawsto the attaching portion of the frame. The jaw attaching means has arotatable coupling portion for integrally holding both the jawsindependent of the pin portion and the frame. (Refer to PatentLiterature 1, for example.)

As a result, when a scrap to be cut is cut, the scrap to be cut can becut such that a portion cut from an end face of the scrap is rectangularas viewed in a plane. However, the width of the cut is identical withthe width of a jaw for destruction biting inward. A more specificdescription will be given. When the jaw for destruction of a pair ofjaws bites inward, the outside destruction jaw is rubbed against bothsides of the former jaw. By rubbing between the cutting edges of thesejaws, the scrap to be cut can be continuously cut as if paper were cutwith scissors. Therefore, it is possible to save time and labor incutting a scrap to be cut, such as a steel plate, and enhance theefficiency of the cutting work.

CITATION LIST Patent Literature

Patent Literature 1: Japanese Patent Publication No. Hei 6(1994)-92705

SUMMARY OF INVENTION Technical Problem

However, these conventional shearing machines for cutting pose a problemwhen an aircraft, such as an airliner, using a high-strength aluminumalloy or the like is dismantled. When an attempt is made to pinch andcut a high-strength aluminum alloy, there are cases where a cutting edgedoes not get into the scrap to be cut at start of shearing and as aresult, the alloy cannot be favorably pinched and cut. Especially, inthe body and wings, such as a main wing, of an aircraft, riveting isadopted and a large number of rivets are used to join the body and thewings together instead of welding. For this reason, because of riveting,the tip of a cutting edge cannot favorably bite at start of shearing.Even though a cutting edge favorably bites, a large burden is imposed onthe cutting edge in a favorable rubbing state and the workpiece cannotbe pinched and cut sometimes.

It is an object of the present invention to obtain a shearing machinefor dismantling large aircrafts and a working vehicle for dismantlinglarge aircrafts suitable for dismantling large aircrafts, such asairliners, using a high-strength aluminum alloy or the like.

Solution to Problem

A shearing machine for dismantling large aircrafts of the first aspectof the present invention is a shearing machine equipped with: a firstjaw portion and a second jaw portion that shear an object to be shearedwith shearing blades provided such that the shearing blades arerelatively rotated between an open position and a closed position; and ahydraulic driving means that rotates the first jaw portion and/or thesecond jaw portion.

As the shearing blades of the first jaw portion, the shearing machineincludes:

a tip blade that includes a point blade and a pair of tapered blades,has the maximum width as the thickness perpendicular to the rotationdirection of the first jaw portion and is positioned in the tip area ofthe first jaw portion, and whose point bites into an object to besheared;

a pair of first parallel shearing blades adjoining to the tip blade anddisposed in both sides of the first jaw portion; and

a pair of second parallel shearing blades each bent at an obtuse angleto an attaching portion of each of the first parallel shearing bladesand disposed in both sides of the first jaw portion.

The tip blade includes:

the point blade having an end face that is disposed at the tip of thefirst jaw portion and is abutted first against an object to be sheared,and whose blade width is smaller than the thickness of the first jawportion and a pair of tip tapered blades that are disposed on both sidesof the end face and whose blade width is continuously increased towardthe rear end; and

the pair of tapered blades that are bent at an obtuse angle torespective attaching portions of the rear end faces of the tip taperedblades of the point blade and are disposed such that a distancetherebetween is increased toward each of the first parallel shearingblades.

As the shearing blades of the second jaw portion, the shearing machineincludes:

a groove portion that penetrably receives all of the tip blade and thepair of first parallel shearing blades and part of each of the pair ofsecond parallel shearing blades during relative movement with the firstjaw portion;

a tip blade receiving blade disposed on an inner wall surface of thegroove portion except an area where the first parallel shearing bladespenetrate so as to border on three sides by the outer circumferentialsurface of the penetrating tip blade;

a pair of first parallel shearing blade receiving blades respectivelydisposed along the inner wall surface of the groove portion in an areawhere both the outer circumferential surfaces of the first parallelshearing blades penetrate; and

a pair of second parallel shearing blade receiving blades respectivelydisposed along the inner wall surface of the groove portion in an areawhere both the outer circumferential surfaces of the second parallelshearing blades penetrate.

In a shearing machine for dismantling large aircrafts of the secondaspect of the present invention, the hydraulic drive system in the firstaspect of the present invention separately includes a first hydraulicdriving means for rotating the first jaw portion and a second hydraulicdriving means for rotating the second jaw portion.

In a shearing machine for dismantling large aircrafts of the thirdaspect of the present invention, the tip blade receiving blade in thefirst or second aspect of the present invention includes: a widthreceiving blade opposed to the periphery of the end face of the pointblade; a pair of tip tapered blade receiving blades rubbed against thetip tapered blades of the point blade; and a pair of tapered bladesreceiving blades rubbed against the pair of tapered blades.

In a shearing machine for dismantling large aircrafts of the fourthaspect of the present invention, the point blade receiving blade portioncomprised of the width receiving blade of the tip blade receiving bladeand the pair of tip tapered blade receiving blades in the third aspectof the present invention is disposed such that the point blade receivingblade portion is inclined from a surface of the second jaw portionopposed to the first jaw portion toward a direction opposed to the firstjaw portion.

A working vehicle for dismantling large aircrafts of the fifth aspect ofthe present invention is constructed by attaching a shearing machine fordismantling aircrafts in the first to fourth aspects of the presentinvention to the tip of a hydraulically actuated boom swivelably andlowerably/raisably mounted on an automotive vehicle.

Advantageous Effects of Invention

The present invention brings about an advantageous effect that ashearing machine for dismantling large aircrafts and a working vehiclefor dismantling large aircrafts suitable for dismantling largeaircrafts, such as airliners, using a high-strength aluminum alloy orthe like can be obtained.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is an explanatory drawing illustrating a configuration of animplementation of an aircraft for dismantling working vehicle equippedwith a shearing machine dismantling large aircrafts of the presentinvention.

FIG. 2 is an explanatory drawing illustrating a configuration of theshearing machine for dismantling large aircrafts shown in FIG. 1.

FIGS. 3(a) to 3(c) are an enlarged view, a side view, and a plan view ofthe tip blade of the first jaw portion of the shearing machine fordismantling large aircrafts shown in FIG. 2,

FIG. 3(d) is a side view of the first jaw portion, and FIG. 3(e) is aplan view showing the tip blades of the first jaw portion.

FIG. 4(a) is an enlarged plan view, FIG. 4(b) is a side view, and FIG.4(c) is a plan view of FIG. 4(b) of the tip blade receiving blade of thesecond jaw portion shown in FIG. 2.

FIGS. 5(a) to 5(d) are explanatory drawings illustrating shearingoperation of a principal part of the shearing machine for dismantlinglarge aircrafts shown in FIG. 2.

FIGS. 6(a) to 6(d) are explanatory drawings illustrating a configurationof a shearing machine for dismantling large aircrafts in anotherimplementation.

DESCRIPTION OF EMBODIMENTS

The present invention is a shearing machine equipped with: a first jawportion and a second jaw portion that shear an object to be sheared withshearing blades outfitted such that the shearing blades are relativelyrotated between an open position and a closed position; and a hydraulicdriving means that rotates the first jaw portion and/or the second jawportion. As the shearing blades of the first jaw portion, the shearingmachine includes: a tip blade that has a maximum width identical withthe thickness of the first jaw portion and whose point bites into anobject to be sheared; a pair of first parallel shearing blades adjoiningto the tip blade and respectively disposed on both sides of the firstjaw portion; and a pair of second parallel shearing blades bent at anobtuse angle to an attaching portion of the first parallel shearingblades and respectively disposed on both sides of the first jaw portion.

Further, as the shearing blades of the second jaw portion, the shearingmachines includes: a groove portion that penetrably receives all of thetip blade and the pair of first parallel shearing blades and part ofeach of the pairs of second parallel shearing blades during relativemovement with the first jaw portion; tip blade receiving blades disposedon the inner wall surface of the groove portion except an area where thefirst parallel shearing blades penetrate so as to border on three sidesby the outer circumferential surface of the tip blade; a pair of firstparallel shearing blade receiving blades respectively disposed along theinner wall surface of the groove portion in an area where both the outercircumferential surfaces of the first parallel shearing bladespenetrate; and a pair of second parallel shearing blade receiving bladesrespectively disposed along the inner wall surface of the groove portionin an area where both the outer circumferential surfaces of the secondparallel shearing blades penetrate.

Thus, the point of the tip blade of the first jaw portion is abuttedagainst an object to be sheared at start of shearing and pressure fromthe hydraulic drive system can be concentrated on the point. For thisreason, a large aircraft, such as an airliner, using a high-strengthaluminum alloy or the like can also be dismantled with ease. A morespecific description will be given. Only the point of the tip blade ofthe first jaw portion is abutted against the high-strength aluminumalloy of the large aircraft to apply hydraulic pressure in aconcentrated manner. As a result, a pierced hole is formed. Subsequentlyto the formed pierced hole, favorable shearing can be achieved by thefirst parallel shearing blades and the first parallel shearing bladereceiving blades.

The point of the tip blade of the first jaw portion is substantiallyperpendicularly pressed against an object to be sheared. Therefore, thepoint is not displaced from the pressing spot and hydraulic pressure canbe favorably concentrated on the pressing spot. A more specificdescription will be given. To cut the body and wings, such as the mainwing, of an aircraft where riveting is adopted instead of welding and alarge number of rivets are used to join the body and the wings together,the following procedure is taken. The point of the tip blade of thefirst jaw portion is pressed against a cutting spot and pressure isconcentrated on the point portion. Thus, the point is not displaced fromthe pressing spot and a pierced hole is easily formed by the point. Thehigh-strength aluminum alloy is sheared by the first parallel shearingblades and second parallel shearing blades behind the tip blade.

Such a shearing machine of the present invention is provided as the tipblade with: a point blade having an end face that is disposed at the tipof the first jaw portion and is abutted first against an object to besheared and whose blade width is smaller than the thickness of the firstjaw portion: a pair of tip tapered blades that are disposed on both sideof the end face and whose blade width is continuously increased towardthe rear end; and a pair of tapered blades that are bent at an obtuseangle to respective attaching portions of the tip tapered blades of thepoint blade and are disposed such that a distance therebetween isincreased toward the respective first parallel shearing blades.

Thus, the end face of the point blade of the first jaw portion isabutted first against an object to be sheared to pierce a hole in thehigh-strength aluminum alloy. The pair of tip tapered blades widen thepierced hole and further widen the width of the pierced hole to thewidth of the first parallel shearing blades while cutting operation isperformed with the pair of tapered blades. Thus, a rivet joined partjoined with a large number of rivets can be ruptured while a largenumber of pierced holes are formed by the end face of the point blade bydriving the first jaw portion little by little. After the passage by therivet joined part area, the cut is widened to the width between thefirst parallel shearing blades while cutting operation is performed withthe pair of tapered blades and the high-strength aluminum alloy issheared by the first parallel shearing blades and the second parallelshearing blades.

The first jaw portion and second jaw portion of a shearing machine ofthe present invention only have to be so designed that an object to besheared is sheared with shearing blades outfitted such that the shearingblades are relatively rotated between an open position and a closedposition. The first jaw portion and the second jaw portion may berespectively rotated by a hydraulic driving means comprised of ahydraulic piston and a cylinder or only either jaw portion may berotated by a single hydraulic driving means.

However, when the point of the point blade is substantiallyperpendicularly pressed against an object to be sheared, the point isnot displaced from the pressing spot and pressing force from a hydraulicdriving means is favorably concentrated on the pressing spot on theobject to be sheared. Therefore, it is desirable to rotate both thefirst jaw portion and the second jaw portion and adjust anopening/closing angle of the second jaw portion relative to the point ofthe point blade of the first jaw portion so that the point of the pointblade is substantially perpendicularly pressed against even a thickobject to be sheared. Hence, a hydraulic drive system of the presentinvention is preferably separately provided with a first hydraulicdriving means for rotating the first jaw portion and a second hydraulicdriving means for rotating the second jaw portion.

As a shearing blade of the first jaw portion, a tip blade of the presentinvention only has to have a maximum width identical with the thicknessof the first jaw portion and to be so designed that a point thereofbites into an object to be sheared. A point blade is preferably providedwith: an end face that is disposed at the tip of the first jaw portionand is abutted first against an object to be sheared and whose bladewidth is smaller than the thickness of the first jaw portion; and a pairof tip tapered blades that are disposed on both sides of the end faceand whose blade width is continuously increased toward the rear end. Thetip tapered blades of the point blade are provided at the rear end facewith a pair of tapered blades that are bent at an obtuse angle torespective attaching portions and are disposed in a direction in which adistance therebetween is increased toward the respective first parallelshearing blades. Thus, shearing stress is favorably produced on the endface whose width is smaller than the thickness of the first jaw portionand the width receiving blade by pressing force from the hydraulic drivesystem and the point of the tip blade easily bites into even an objectto be sheared of a high-strength aluminum alloy and forms a pierced holethere.

In a tip blade receiving blade of the present invention, a point bladereceiving blade portion comprised of a width receiving blade and a pairof tip tapered blade receiving blades is disposed such that the pointblade receiving blade portion is inclined in a direction opposed to thefirst jaw portion. Thus, it is possible to prevent the point from beingdisplaced from a pressing spot and more favorably concentrate hydraulicpressure on the pressing spot by adjusting an inclination angle so thata pressing direction of the end face of the point blade is perpendicularto an object to be sheared.

With respect to a shearing angle, which is an angle of an openingbetween blades opposed to each other of shearing blades of the presentinvention, the following takes places in case of linear blades: forcerequired for cutting is reduced by angling either cutting tool (acutting tool on the movable side in ordinary cases) and a neat cut edgeis obtained by continuously proceeding with cutting operation in onedirection. By increasing a shearing angle, a “maximum shearing force” isreduced and the power of a shear (cutting machine) can be reduced. As ashearing angle is increased, however, a bend or a twist is increasedduring cutting, the dimensions of a plate differs between start ofcutting and end of cutting, or other like phenomena occur and thequality or grade of a sheared product is impaired.

Further, the quality of a cut edge, required shearing force or lateralforce, or the like varies depending on the size of a gap (clearance)between opposite blades of the shearing blades of the present invention.For some shears, a standard value for clearance value is often specifiedwith respect to a thickness of a plate to be cut or some steel typecategories. However, since the property (quality) of a cut edge variesdepending on a difference in mechanical property of a material to becure, machine accuracy, blank holding force, or the like, it isadvisable to select an optimal clearance. For example, for a platethickness of 20 mm, a clearance equal to 20% of the thickness is taken.

A dismantling working vehicle for large aircrafts can be obtained byattaching a shearing machine for dismantling large aircrafts of thepresent invention to the tip of a hydraulically actuated boom swivelablyand lowerably/raisably mounted on an automotive vehicle.

Example

FIG. 1 is an explanatory drawing illustrating a configuration of anexample of a dismantling working vehicle for aircrafts equipped with ashearing machine for dismantling large aircrafts of the presentinvention. FIG. 2 is an explanatory drawing illustrating a configurationof the shearing machine for dismantling large aircrafts shown in FIG. 1.FIGS. 3(a) to 3(c) are an enlarged view, a side view, and a plan view ofa tip blade of a first jaw portion of the shearing machine fordismantling large aircrafts shown in FIG. 2. FIG. 3(d) is a side view ofthe first jaw portion, and FIG. 3(e) is a plan view of showing the tipblades of the first jaw portion. FIG. 4(a) is an enlarged plan view,FIG. 4(b) is a side view, and FIG. 4(c) is a plan view of a tip bladereceiving blade of a second jaw portion shown in FIG. 2. FIGS. 5(a) to5(d) are explanatory drawings illustrating shearing operation of aprincipal part of the shearing machine for dismantling large aircraftsshown in FIG. 2. FIGS. 6(a) to 6(d) are explanatory drawingsillustrating a configuration of a shearing machine for dismantling largeaircrafts in another implementation.

As shown in FIG. 1, a dismantling working vehicle 10 for large aircraftsin the present example is comprised of: an automotive vehicle 11; and adismantling shearing machine 20 attached to the tip of a hydraulicallyactuated boom 14 swivelably and lowerably/raisably mounted on theautomotive vehicle 11. More specifically, the automotive vehicle 11 ismounted with a swiveling stage 12 driven by engine output or electricpower supplied from an external power source.

The stage 12 is provided on the front left side of the stage with adriver's cabin 13 such that the cabin faces forward during driving. Atthe central part of the stage, the hydraulically actuated boom 14 isrotatably supported by a derricking cylinder 15 such that the boom canbe raised/lowered and the boom 14 has at the tip thereof the dismantlingshearing machine 20 rotatably supported in a lowerable/raisable mannerby a hydraulic driving means 16 comprised of a hydraulic piston and acylinder. An oil pressure generating device 17 is mounted behind thestage 12. When the vehicle 11 is transported by a trailer truck or thelike, the boom 14 is lowered or raised to a predetermined angle orfolded.

As illustrated in FIG. 2, the shearing machine 20 for dismantling largeaircrafts is freely held on a frame device 21 including a frame baserotated by a rotating means, not shown. The frame device 21 is attachedsuch that the frame device can be inclined toward the hydraulicallyactuated boom 14 at a fulcrum 22. The frame device 21 is rotated andlowered/raised to various angles by driving the rotating means and thehydraulic driving means 16 through operation from the driver's cabin 13.

The dismantling shearing machine 20 includes: a body portion 23 havingtwo panels installed on the frame base of the frame device 21; a firstjaw portion 25 and a second jaw portion 26 disposed between the twopanels of the body portion 23 and relatively rotated around a fulcrum 24between an open position and a closed position; a first hydraulicdriving means 27 that rotates the first jaw portion 25 around thefulcrum 24; and a second hydraulic driving means 28 that rotates thesecond jaw portion 26 around the fulcrum 24.

The first jaw portion 25 includes: as shearing blades located ahead ofthe fulcrum 24, a tip blade whose point bites first into an object to besheared; a pair of first parallel shearing blades 33 that are bent at anobtuse angle to the direction of biting of the tip blade andrespectively disposed on both sides of the first jaw portion 25; and apair of second parallel shearing blades 34 that are bent at an obtuseangle to an attaching portion of the first parallel shearing blades andrespectively disposed on both sides of the first jaw portion 25. The tipblade is composed of a point blade 31 and a pair of tapered blades 32.

As shearing blades located ahead of the fulcrum 24, the second jawportion 26 also has: a groove portion 35 which all of the tip blade andthe pair of first parallel shearing blades 33 and part of each of thepair of second parallel shearing blades 34 penetrate during relativemovement with the first jaw portion 25 and which is disposed so as tosurround the outer circumferential surface of the tip blade; a tip bladereceiving blade 36 that surrounds an outer circumference which the tipblade penetrates and is disposed along the inner wall surface of thegroove portion 35 except an area where the first parallel shearing bladeareas penetrate; a pair of first parallel shearing blade receivingblades 38 respectively disposed along the inner wall surface of thegroove portion 35 in an area where each of the first parallel shearingblades 33 penetrates; and a pair of second parallel shearing bladereceiving blades 39 respectively disposed along the inner wall surfaceof the groove portion 35 in an area where each of the second parallelshearing blades 34 penetrates.

A more specific description will be given. The tip portion of the firstjaw portion 25 in FIG. 2 is detachably attached to the tip portion ofthe first jaw portion 25. As shown in FIGS. 3(a) to 3(e), the pointblade 31 of the tip blade has an end face 31 a whose blade width issmaller than the thickness of the first jaw portion 25 and which can beabutted against an object to be sheared. As shown in FIGS. 4(a) to 4(c),the longitudinal side of the end face 31 a in the direction of width isdisposed opposite to the width receiving blade 36 a of the tip receivingblade 36 of the second jaw portion 26 and the end face 31 a is caused tomake a hole by shearing between these width sides.

A pair of tip tapered blades 31 b are disposed on both sides of the endface 31 a such that the blade width is continuously increased as they gotowards the rear end. The outer ridge portions of the pair of tiptapered blades 31 b act as a cutting portion. When the first jaw portion25 and the second jaw portion 26 are rotated and meet together, the pairof tip tapered blades 31 b and the tip tapered blade receiving blades 36b are rubbed with each other and an object to be sheared is sheared.

An attaching bolt (not shown) for attaching the point blade 31 of thetip blade to the first jaw portion 25 can be removed and the point blade31 can be rotated by 180° around an axis going through the center of theend face 31 a. Thus, when the blade of one end face 31 a and one tiptapered blade 31 b are worn, they can be replaced with the opposite endface 31 a and tip tapered blade 31 b and the life of the point blade 31can be doubled.

As shown in FIG. 2 and FIG. 3(a), a pair of tapered blades 32 aredisposed at the respective rear end faces of the pair of tip taperedblades 31 b of the first jaw portion 25. The pair of tapered blades 32are bent at an obtuse angle to respective attaching portions of the pairof tip tapered blades and disposed such that a distance therebetween isincreased toward the subsequent respective first parallel shearingblades 33. As shown in FIG. 4, tapered blade receiving blades 37 areprovided on the second jaw portion 26 in positions opposite the taperedblades 32.

The pair of tapered blades 32, the pair of first parallel shearingblades 33, and the pair of second parallel shearing blades 34 and thepair of tapered blade receiving blades 37, the pair of first parallelshearing blade receiving blades 38, and the pair of second parallelshearing blade receiving blades 39 opposed thereto are formed of arectangular parallelepiped, replaceable blade and their fourlongitudinal sides are configured as a shearing blade. Therefore, thelife of each shearing blade can be quadruplicated by removing individualattaching bolts (not shown), replacing each shearing blade with another,and attaching them.

A description will be given to motion of the first jaw portion 25 andthe second jaw portion 26 with a case where a wing-shaped object 50 tobe sheared is to be sheared being taken as an example. As shown in FIG.5a , the first jaw portion 25 and the second jaw portion 26 as areopened are gradually closed. In this case, the first jaw portion 25 andthe second jaw portion 26 are so adjusted that the end face 31 a of thepoint of the tip blade 31 of the first jaw portion 25 is pressed againstthe object 50 to be sheared substantially in a perpendicular direction(FIG. 5(a)).

As shown in FIG. 5(b), the first hydraulic driving means 27 and thesecond hydraulic driving means 28 are driven from the state shown inFIG. 5a to press and cause the end face 31 a to bite into the object 50to be sheared. A more specific description will be given. As shown inFIGS. 3(a) to 3(c), the tip blade 31 has a width smaller than thethickness of the first jaw portion 25 and has the end face 31 a that canbe abutted against an object to be sheared substantially in aperpendicular direction. The tip blade is abutted against the object 50to be sheared substantially in a perpendicular direction and the firstjaw portion 25 and the second jaw portion 26 are rotated by therespective hydraulic driving means 27, 28. For this reason, pressingforce favorably produces shearing stress and the point of the tip bladeeasily bites into even the object to be sheared of a high-strengthaluminum alloy, a pierced hole being thereby formed there.

As the tip blade 31 bites, the pierced hole is gradually widened. Whilethe workpiece is sheared by the tip tapered blade receiving blades 36 bof the tip blade receiving blade 36, as shown in FIG. 5b to FIG. 5c , athrough hole is formed through shearing by the first parallel shearingblades 33 and first parallel shearing blade receiving blades 38 on thefulcrum 24 side. As shown in FIG. 5d , the object 50 to be sheared issheared through shearing by the second parallel shearing blades 34 andthe second parallel shearing blade receiving blades 39.

FIGS. 6(a) to 6(d) are explanatory drawings illustrating a configurationof a shearing machine for dismantling large aircrafts in anotherexample; FIG. 6(a) is a side view; FIG. 6(b) is a plan view of thesecond jaw portion 66, FIG. 6(c) is an enlarged view of a tip blade; andFIG. 6(d) is an enlarged view of a tip blade receiving blade. In theshearing machine 60 for dismantling large aircrafts in the example shownin FIGS. 6(a) to 6(c), as in the example shown in FIG. 2, a first jawportion 65 and a second jaw portion 66 are disposed between two panelsof a body portion 63 and relatively rotated around a fulcrum 64 betweenan open position and a closed position by a first hydraulic drivingmeans 67 and a second hydraulic driving means 68.

Like the first jaw portion 25 in FIG. 2, the first jaw portion 65includes a tip blade, a pair of first parallel shearing blades 73, and apair of second parallel shearing blades 74. At the point blade 71 of thetip blade, there are provided an end face 71 a and a tip tapered blade71 b. At the rear end thereof, there are provided a pair of taperedblades 72, a pair of first parallel shearing blades 73, and a pair ofsecond parallel shearing blades 74. On the inner wall of the grooveportion 75 which the tip of the first jaw portion 65 penetrates, thesecond jaw portion 66 includes: a tip blade receiving blade 76 comprisedof a width receiving blade 76 a and a tip tapered blade receiving blade76 b; tapered blade receiving blades 77; first parallel shearing bladereceiving blades 78; and second parallel shearing blade receiving blades79. The tip blade is composed of a point blade 71 and a pair of taperedblades 72.

In such a second jaw portion 66, a tip blade receiving blade 76 portioncomprised of the width receiving blade 76 a and the pair of tip taperedblade receiving blades 76 b is disposed such that the tip bladereceiving blade portion is inclined in a direction opposed to the firstjaw portion 65. Thus, it possible to prevent the point from displacingfrom a pressing spot and favorably concentrate hydraulic pressure on thepressing spot by adjusting an inclination angle so that the pressingdirection of the end face of the point blade is perpendicular to anobject to be sheared.

REFERENCE SIGNS LIST

-   -   10: dismantling working vehicle for large aircrafts,    -   11: automotive vehicle,    -   12: swiveling stage,    -   13: driver's cabin,    -   14: hydraulically actuated boom,    -   15: derricking cylinder,    -   16: hydraulic driving means,    -   17: oil pressure generating device,    -   20, 60: dismantling shearing machine,    -   21: frame device,    -   22: fulcrum,    -   23, 63: body portion    -   24, 64: fulcrum,    -   25, 65: first jaw portion,    -   26, 66: second jaw portion,    -   27, 67: first hydraulic driving means,    -   28, 68: second hydraulic driving means,    -   31, 71: point blade,    -   31 a, 71 a: end face,    -   31 b, 71 b: tip tapered blade,    -   32, 72: tapered blade,    -   33, 73: first parallel shearing blade,    -   34, 74: second parallel shearing blade,    -   35, 75: groove portion,    -   36, 76: tip blade receiving blade,    -   36 a, 76 a: width receiving blade,    -   36 b, 76 b: tip tapered blade receiving blade,    -   37, 77: tapered blade receiving blade,    -   38, 78: first parallel shearing blade receiving blade,    -   39, 79: second parallel shearing blade receiving blade,    -   50: object to be sheared,

The invention claimed is:
 1. A shearing machine for dismantling largeaircrafts comprising: a first jaw portion and a second jaw portion thatshear an object to be sheared by shearing blades outfitted such that theshearing blades are relatively rotated between an open position and aclosed position; and a hydraulic driving means that rotates the firstjaw portion and/or the second jaw portion, wherein the shearing bladesof the first jaw portion includes: a tip blade which has a width thesame as a thickness perpendicular to a rotation direction of the firstjaw portion, is disposed in a tip area of the first jaw portion, andbites into an object to be sheared; and a pair of tapered blades thatadjoin the tip blade and are respectively disposed on two sides of thefirst jaw portion; a pair of first parallel shearing blades that adjointo the respective tapered blades and are respectively disposed on twosides of the first jaw portion; and a pair of second parallel shearingblades that adjoin and are angled at an obtuse angle to the firstparallel shearing blades and are respectively disposed on two sides ofthe first jaw portion, wherein the tip blade has an end face that isdisposed at a tip of the first jaw portion to abut first against theobject to be sheared, and a pair of tip tapered cutting edges that aredisposed on two sides of the end face, the tip blade having a bladewidth continuously increasing toward a rear end; and the pair of taperedblades are angled at an obtuse angle to the tip tapered cutting edgesand disposed in a direction in which a distance between the pair oftapered cutting edges is increased rearward, and wherein the shearingblades of the second jaw portion includes: a groove portion thatpenetrably receives all of the tip blade, the pair of tapered blades andthe pair of first parallel shearing blades and part of each of the pairof second parallel shearing blades during relative movement with thefirst jaw portion; a tip blade receiving blade disposed on an inner wallsurface of the groove portion having a shape corresponding to the tipblade so as to face an outer circumferential surface of the tip blade; apair of first parallel shearing blade receiving blades respectivelydisposed along the inner wall surface of the groove portion in an areawhere two outer circumferential surfaces of the first parallel shearingblades penetrate; and a pair of second parallel shearing blade receivingblades respectively disposed along the inner wall surface of the grooveportion in an area where two outer circumferential surfaces of thesecond parallel shearing blades penetrate.
 2. The shearing machine fordismantling large aircrafts according to claim 1, wherein the hydraulicdrive system separately includes a first hydraulic driving means forrotating the first jaw portion and a second hydraulic driving means forrotating the second jaw portion.
 3. The shearing machine for dismantlinglarge aircrafts according to claim 1, wherein the tip blade receivingblade includes a width receiving blade opposed to a periphery of the endface of the tip blade, a pair of tip tapered cutting edge receivingblades that rub together with the tip tapered cutting edges of the tipblade, and a pair of tapered blade receiving blades that rub togetherwith the pair of tapered blades, which are formed separately.
 4. Theshearing machine for dismantling large aircrafts according to claim 1,wherein the hydraulic drive system means separately includes a firsthydraulic driving means for rotating the first jaw portion and a secondhydraulic driving means for rotating the second jaw portion, wherein thetip blade receiving blade includes a width receiving blade opposed to aperiphery of the end portion face of the tip blade, a pair of tiptapered cutting edge receiving blades that rub together with the tiptapered cutting edges of the tip blade, and a pair of tapered bladereceiving blades that rub together with the pair of tapered blades.
 5. Aworking vehicle for dismantling large aircrafts, comprising the shearingmachine for dismantling aircrafts according to claim 1, and ahydraulically actuated boom swivelably and lowerably/raisably mounted onan automotive vehicle, the shearing machine being attached to the boom.